A Phase 2 Randomized Controlled Trial of Single-Agent Hydroxyurea Versus Thalidomide Among Adult Transfusion Dependent β Thalassemia Patients

Abstract

Hydroxyurea and low dose thalidomide are low-cost, easily accessible Hb F inducing agents that have been found to decrease transfusion dependency among transfusion-dependent thalassemia patients. However, these drugs have not much been explored in a randomized controlled setting. The objective of this study was to determine the efficacy and safety of hydroxyurea and low dose thalidomide in adult transfusion dependent β thalassemia. A total of 39 transfusion dependent β thalassemia patients were randomized into three arms: Arm A (Hydroxyurea 500 mg/day), Arm B (thalidomide 50 mg/day), and Control Arm. The primary outcome was rise in haemoglobin at 24-weeks from the baseline levels. The mean age of the cohort was 26.9 ± 4.7 years. Total 13 patients (33.3%) were splenectomised. The mean rise of haemoglobin at the end of 24 weeks was 0.18 ± 0.645 g/dl, 0.56 ± 1.343 g/dl, and − 0.31 ± 0.942 g/dl in Arm A, Arm B and control arm, respectively, p = 0.127. The mean volume of blood transfused per unit body weight in 24 weeks was significantly less in the thalidomide arm compared with the control arm (p = 0.035). Abdominal pain (Grade 1–2, 23.1%) and pruritus (Grade 1, 15.4%) were the main adverse events in hydroxyurea arm, whereas somnolence was the main side effect noted in the thalidomide arm (Grade 1–2, 78.3%). Single agent hydroxyurea or thalidomide is ineffective in increasing haemoglobin and decreasing transfusion burden among majority of the adult transfusion dependent thalassemia patients.